SAN DIEGO – .
In the 1990s, clinicians used nonabsorbable sutures for thread lifts, including polypropylene-barbed threads, which caused adverse events ranging from extrusion and migration to thread expulsion, dimpling, granuloma formation, and prolonged pain, Dr. DiGiorgio, a laser and cosmetic dermatologist who practices in Boston, said at the annual Masters of Aesthetics Symposium. As a result, the Food and Drug Administration withdrew its approval of contour thread aesthetic procedures in 2009. Since then, the development of absorbable threads made from a hybrid of poly-l-lactic acid (PLLA) and polyglycolide/l-lactide (PLGA), and from polydioxanone (PDO) has led to renewed interest in thread lift procedures.
Dr. DiGiorgio
Dr. Catherine M. DiGiorgio
While a surgical facelift remains the gold standard, “we have some options to offer patients for noninvasive tightening,” Dr. DiGiorgio said. “We have devices that provide minimal downtime and are less costly, but results are inconsistent. Thread lifts, or suspension sutures, also have minimal downtime and are less costly, but the [results are] subtle and not long lasting.”
PLGA/PLLA threads consist of an 18% PLGA and 82% PLLA monofilament with bidirectional cones that shift the tissue. They are available in 8, 12, or 16 cones spaced 5-8 mm apart on either side of a 2-cm central cone-free area. “There is a 12-cm, 23-gauge needle on either side of the thread, to allow for insertion,” she explained. “These cones stimulate types I and II collagen, which results in collagenesis. The skin encapsulates the cones, resulting in lasting volume and contour.”
PDO threads, meanwhile, are biodegradable by hydrolysis over 4-8 months. They are inserted with a cannula or a needle and vary based on length, diameter, twined vs. braided, coned vs. barbed, and twisted vs. smooth. “The barbed PDO threads are what I use the most,” Dr. DiGiorgio said. “They provide slight tissue repositioning by anchoring and gripping.”
In 2019, researchers in Korea published results of a study that evaluated the collagen-producing effects of powdered PDO injection, compared with PLLA injection, in a murine model. They found that while both PDO and PLLA induced granulomatous reactions and collagen formation, PDO resulted in slightly more collagen formation than PLLA.
Dr. DiGiorgio, who transitioned to using PDO threads after first using the PLLA/PLGA threads, said that both are effective. “I find PDO threads to be easier. They’re less costly for me, they’re less costly for the patient, and the results are about equivalent.”
Absorbable threads are indicated for the cheek, jawline, neck, lips, forehead, and brow. She finds them most useful “for the lower face, below the nasolabial fold down to the jawline, for improvement of the jowls,” she said. “I don’t think they really work on the neck.”
As with any cosmetic procedure, patient selection is key. According to Dr. DiGiorgio, the patient should have specific and segmental areas of facial laxity amenable to lifting and recontouring along a straight-line vector, adequate dermal thickness, and appropriate expectations for the level of correction. “I like to re-volumize with filler before performing thread lifts to make sure that volume is restored, because you can’t really provide lift to someone with significant volume loss,” she said.